The conventional method of producing strip or sheets of molybdenum from a metal powder includes first making a slab. This is achieved by a compaction process, such as Cold-Isostatic Pressing, Vacuum Hot Pressing, or Die Pressing. The resulting thick slabs of molybdenum about 1.0″ to 4.0″ thick are then sintered at temperatures in the 1400° C. to 2300° C. range and then hot rolled at 1100° C. to 1400° C. range into plates about 0.4″ to 0.6″ thick. The plates are then annealed above the recrystallization temperature of the material and hot rolled again into sheets at slightly lower temperatures (1000° C. to 1250° C.) to a thickness close to 0.050″. Multiple intermediate chemical etching and cleaning steps are carried out to remove embedded iron particles and surface oxides from the previous hot rolling operations. Subsequent rolling is carried out at warm working temperatures in the 200° C. to 500° C. range (lower temperatures are used as the material is progressively worked to thinner gauge). After approximately 50% reduction at the warm working temperatures, the material can be cold worked at room temperature with intermediate stress relief anneals.
Therefore, the conventional process for making the molybdenum-based thin strips from metal powders requires several hot rolling, chemical etching, and cleaning operations. Such an energy intensive process which also requires the use of harmful chemicals is costly, potentially hazardous, and environmentally unfriendly. Thus, there is a need for improved processes for manufacturing molybdenum-containing sheet.